docs: def results_overall_metrics(self):
          """Overall metrics
  
          Returns
          -------
          dict
              results in a dictionary format
  
          """
  
          # F-measure
          if self.overall['Nref'] > 0:
              precision = metric.precision(
                  Ntp=self.overall['Ntp'],
                  Nsys=self.overall['Nsys']
              )
  
              recall = metric.recall(
                  Ntp=self.overall['Ntp'],
                  Nref=self.overall['Nref']
              )
  
              f_measure = metric.f_measure(
                  precision=precision,
                  recall=recall
              )
  
          else:
              precision = None
              recall = None
              f_measure = None
  
          y_true = []
          y_score = []
          for tag_id, tag_label in enumerate(self.tag_label_list):
              y_true += self.y_true[tag_label]
              y_score += self.y_pred_score[tag_label]
  
          if y_score:
              eer = metric.equal_error_rate(
                  y_true=y_true,
                  y_score=y_score
              )
  
          else:
              eer = None
  
          return {
                  'count': {
                      'Nref': self.overall['Nref'],
                      'Nsys': self.overall['Nsys'],
                  },
                  'f_measure': {
                      'f_measure': f_measure,
                      'precision': precision,
                      'recall': recall,
                  },
                  'eer': {
                      'eer': eer
                  }
  
          }